Premnath fell in love with actress Bina Rai during the filming of Aurat and later married her. Raj Kapoor's wife Krishna Nath was sister of Prem Nath. So Premnath and Raj Kapoor were brothers-in-law.
They also shared a professional bond as Premnath was a part of many films directed by Raj Kapoor.
These include Aag, Awara, Barsaat and Bobby. They were also seen together in Dharam Karam which was directed by Randhir Kapoor.
In Awara, Premnath plays a cameo in the song Naiyya Teri Majhdar. Besides this Raj Kapoor played a cameo of a gypsy singer in Chandi Sona which also starred Premnath. Chandi Sona was directed by Sanjay Khan and starred himself and Parveen Babi as the main lead.
In addition of being relatives Premnath and Raj Kapoor were good friends and were often seen together at social events and industry functions.
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